JP3359862B2 - Locking device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a locking device for swingably supporting a supported member with respect to a supporting member. More specifically, the present invention relates to a locking device capable of fixing tilting.

[0002]

2. Description of the Related Art There is a chair provided with a locking device with a lock mechanism which enables a seat and a backrest of a chair to be rockable back and forth and can fix the seat and the backrest in an inclined state. For example, the locking device shown in FIG. 16 includes a front seat frame 101 fixed to a leg, a rear seat frame 102 swingable with respect to the leg, and a countermeasure for applying a force for returning the rear seat frame 102 to an original position. A lock mechanism 1 comprising a force applying mechanism (not shown) and a gas spring capable of fixing the rear seat frame 102 while being inclined.
07 (see JP-A-4-193108). In this chair, when the lock mechanism 107 is unlocked, the seat 103 and the backrest 105 can be locked. Then, by setting the lock mechanism 107 to the locked state, the seat 103 and the backrest 105 are locked while being inclined.

A chair locking device 201 shown in FIGS. 17 and 18 has a seat receiving member 2 supported on a leg 202.
03, a support shaft 204 rotatably attached to the seat receiving member 203 with the chair width direction as a longitudinal direction, and a support shaft 2
Brackets 206, 206 fixed to both ends of the support shaft 04 to support the seat 205, a swing plate 207 fixed to the center of the support shaft 204, and a compression coil spring for urging the swing plate 207 upward. A reaction force applying mechanism 208 and a lock mechanism (not shown) for locking the seat 205 and the backrest 209 in an inclined state are provided. The lock mechanism here is
For example, a gas spring is mounted on the seat receiving member 203 and the bracket 2.
06 or a bracket 20
A mechanism that allows the shaft member to communicate with the seat member 6 and fixes the shaft member, or a mechanism that locks and locks the lock member provided on the seat member 203 with the gear member fixed to the bracket 206, Bracket 206 side and seat receiving member 20
Various mechanisms can be adopted, such as a mechanism in which several clutch plates are fixed to each of the three sides, and the clutch plates are overlaid and fixed by tightening each clutch plate.

In this chair, the seat 205 and the backrest 209 can be locked by unlocking the lock mechanism. Then, by setting the lock mechanism to the locked state, the seat 205 and the backrest are locked while being inclined.

[0005]

However, in each of the above-described locking devices, the lock of the seat and the backrest is always released when the lock mechanism is in the unlocked state, so that the seat and the backrest can be locked. If the lock mechanism is operated in the unlocked state while the occupant is not tilted and locked, the seat and the backrest may jump up suddenly due to the reaction force of the reaction force applying mechanism.

Accordingly, an object of the present invention is to provide a locking device which can prevent a supported member from suddenly jumping up due to a reaction force of a reaction force applying mechanism during an unlocking operation.

[0007]

In order to achieve the above object, a chair locking device according to a first aspect of the present invention supports a supported member so as to be capable of swinging about a single rotation axis with respect to a supporting member. A locking device for urging the supported member toward the initial position by the reaction force applying mechanism together with a plurality of engagement grooves arranged in the swinging direction of the supported member. A locked member attached to one side and a support member or a locked member of the supported member are slidably mounted in a direction in which the lock member is not attached to the engagement groove so that the lock member is locked when the engagement member is fitted into the engagement groove. A lock member that locks the tilt of the support member, operating means that is switched between a locked position and an unlocked position, and is held at least in the unlocked position, and between the operating means and the lock member. Movement of vignetting by the operating means and transmitted to the locking member, Note and in the direction extracting the locking member from at least the engaging groove so that and a biasing means for resiliently biasing.

Therefore, when the operating means is at the lock position and the lock member is fitted in the engagement groove of the locked member, the lock member straddles the support member or the supported member to which the lock member is attached and the engagement groove. Therefore, the tilting of the supported member is locked. In this state, if no external force is applied to the supported member or only a small external force is applied, the supported member is urged to return to the initial position by receiving a large reaction force of the reaction force applying mechanism. Have been. Here, since the inner wall of the engagement groove of the locked member and the lock member are pressed against each other, the lock member is engaged even if the operating means is operated to the unlock position to pull the lock member out of the engagement groove. Cannot move due to large friction with the inner wall of the groove. For this reason, the biasing means is stored at the same time as the lock of the tilt of the supported member is maintained. As a result, the tilted state of the supported member is so-called self-held.

When an external force is applied to the self-supported supported member to weaken the reaction force by the reaction force applying mechanism, the pressing force between the inner wall of the engagement groove and the lock member is reduced, and the friction is reduced. Power weakens. Further, when the frictional force becomes smaller than the urging force of the urging means in the pulling-out direction of the lock member, the locking member is pulled out of the engagement groove by the urging means. Accordingly, the locked state by the lock member and the engagement groove is released, and the supported member is unlocked and can swing, so that the supported member returns to the initial position by the bias of the reaction force applying mechanism.

[0010] In the locking device according to claim 2 is provided with a position capable of holding the holding member in any of the lock position and the unlock position operation means, Note and biasing means engaging groove the locking member It is characterized in that it is elastically urged in both directions of pulling out from the groove and inserting it into the engagement groove.

Therefore, the supported member can swing with respect to the support member when the operating means is at the unlock position and the lock member is out of the engagement groove of the locked member. Here, when the operating member is operated to the lock position and the lock member is to be inserted into the engagement groove, it is assumed that the lock member is at a position shifted in the swing direction of the supported member with respect to the engagement groove. The lock member comes into contact with the locked member and cannot be fitted into the engagement groove. For this reason, the urging means is charged while the lock member cannot be fitted into the engagement groove. And
When the position of the locked member is shifted in the swinging direction of the supported member by changing the magnitude of the external force applied to the supported member, the locking member is biased when the position of the locking member and the engagement groove is aligned. Is inserted into the engagement groove. As a result, the supported member is locked and cannot swing.

Further, in the locking device according to the third aspect, the urging means includes a switching arm which engages with the lock member in a sliding direction of the lock member, and a switching position between the lock position and the unlock position which is interlocked with the operation means. A switching lever that is switched and held, an elastic body interposed between the switching lever and the switching arm, and a holding member that holds the switching lever in a locked position and an unlocked position are provided.

Therefore, since the elastic member is interposed between the switching arm and the switching lever, the lock member is fitted into the engagement groove and cannot be disengaged from the engagement groove due to the frictional force with the engagement groove. When the switching lever is switched to the unlock position when the arm cannot swing, the switching lever is switched to the unlock position due to deformation of the elastic body, and the position is held by the holding member. At this time, since the elastic body is charged by the deformation, the elastic body is charged when the frictional force between the lock member and the engagement groove is reduced by the external force and the lock member can be released from the engagement groove. The switching arm is swung by force to pull out the lock member from the engagement groove.

On the other hand, when the lock member is disengaged from the engagement groove and the lock member and the engagement groove are displaced in the swinging direction of the supported member and the lock member cannot be fitted into the engagement groove, the switching lever is moved to the lock position. When the switching lever is switched, the switching lever is switched to the lock position by the deformation of the elastic body, and the position is held by the holding member. At this time, since the elastic body is charged by the deformation, when the position of the lock member and the engagement groove is aligned with the swing of the supported member and the lock member can be fitted into the engagement groove, the elastic body is elastically charged. The body swings the switching arm by the accumulating force to insert the lock member into the engagement groove.

Further, in the locking device according to the fourth aspect, the first rotating shaft that rotates integrally with the operating means, and the second rotating shaft that is coaxially arranged with the first rotating shaft and the end portions close to each other.
And the first rotation shaft and the second rotation shaft are integrally rotated.
And a connecting means for rotatably connecting the ends of the rotating shafts to each other.

Accordingly, the function of operating the operating means on the first rotating shaft and the arm operated by the second rotating shaft are supported while preventing the first rotating shaft and the second rotating shaft from falling off. Functions and functions can be shared.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration of the present invention will be described below in detail based on an example of an embodiment shown in the drawings. 1 to 7 show an example of an embodiment in which the locking device 1 of the present invention is mounted on a chair. In this specification, the front-back direction means the front-back direction of the chair, the left-right direction means the left-right direction of the chair, and the up-down direction means the up-down direction of the chair.

The locking device 1 includes a seat as a supported member (in the drawing, a seat which is a core material of the seat) with a center on a support shaft 5 as a rotation shaft with respect to a seat receiving member 3 as a support member. (Only the plate 4 is shown) is swingably supported, and the seat plate 4 is urged toward the initial position by the reaction force applying mechanism 28.

The locking device 1 has a plurality of engagement grooves 7,..., 7 arranged in the swinging direction of the seat plate 4, a locked member 20 attached to the seat plate 4, and a seat receiving member 3. A lock member 8 slidably attached to the engagement groove 7 so as to slide in and out of the engagement groove 7 to lock the tilting of the seat plate 4 when the seat plate 4 is fitted into the engagement groove 7; A lock operation lever 18 as operation means held at an unlocked position, an urging means 24 provided between the lock operation lever 18 and the lock member 8 and transmitting the movement of the lock operation lever 18 to the lock member 8; It has.

This locking device 1 includes a seating member 3 described above, a support shaft 5 fixed to the seating member 3 and separated at two points, for example, a seat plate 4 at both ends, and a support shaft 5. A support plate 6 rotatably mounted and supporting the seat plate 4 at a position forming a vertex of a triangle with both ends of the support shaft 5
And a reaction force applying mechanism 28 having, for example, a compression coil spring 2 for supporting the support plate 6 while urging it upward.

The seat receiving member 3 is supported by the legs 25 and supports the seat plate 4 swingably about the support shaft 5. The seat receiving member 3 includes two arms 26, 26, which extend substantially in a V-shape toward the front side, a base block 59 provided at a rear end to which the arms 26, 26 are coupled, and a base block 59. Leg receiving hole 9 formed in the end block 59 and having a through hole that opens in the vertical direction.
And a groove formed at the front end of each of the arms 26 and 26 and communicating with the chair in the left-right direction and having an open upper side.
And a connecting plate 11 for connecting the arms 26, 26 at the center of each arm 26, 26. The seat receiving member 3 is fixed to the upper end of the leg 25 by pressing the upper end of the rotatable leg 25 into the leg receiving hole 9. The seat receiving member 3 is made of metal and is integrally formed by, for example, casting or welding. In the present embodiment, the seat receiving member 3 is made of metal, but is not limited to this, and may be made of another material such as synthetic resin.

In the support grooves 27, one support shaft 5 protruding left and right of the seat receiving member 3 is fixed non-rotatably by welding, for example. The support shaft 5 rotatably receives and supports the seat plate 4. Note that, for example, armrests or caps can be attached to both ends of the support shaft 5.

The support shaft 5 is an iron pipe having a circular cross section. In this embodiment, the support shaft 5 is an iron pipe.
It is good also as a solid iron bar without being restricted to this. The material of the support shaft 5 is not limited to iron, but may be metal such as aluminum, plastic, or the like. In any case, the seat plate 4 can be supported by the seat receiving member 3. further,
In the present embodiment, the support grooves 27, 27 and the support shaft 5 are fixed by welding. However, the present invention is not limited to this. For example, a set screw that penetrates the support grooves 27, 27 from outside to inside is provided and screwed. You may do it. If this set screw is provided on at least one of the peripheral walls of the two support grooves 27, 27, the support shaft 5 can be fixed to the support grooves 27, 27 so as not to rotate.

In this embodiment, the support shaft 5 is supported by the support grooves 27. However, the present invention is not limited to this. For example, as shown in FIG. It is also possible to form the supporting holes 10 and 10 and insert and support the supporting shaft 5. In this case, the support hole 1
The fixing of the support shaft 5 to the support shaft 5 is performed, for example, by tightening a set screw 21 from the outside to the inside of the peripheral wall forming the support hole 10 to press the support shaft 5 against the inner wall of the support hole 10.

The seat receiving member 3 has a connecting plate 11 for connecting the arms 26, 26 at the center of the arms 26, 26, and an opening 12 formed at the rear side of the connecting plate 11 and extending vertically.
And The connecting plate 11 is connected to the reaction force applying mechanism 28 and supports the seat plate 4 via the reaction force applying mechanism 28 and the support plate 6. The connecting plate 11 includes a reaction force applying mechanism 28.
In order to connect to the central portion, there is provided a concave portion 11a formed in the central portion and having a longitudinal direction in the left-right direction, and a through hole 11b formed in the center of the concave portion 11a. The opening 12
The supporting plate 6 and the connecting plate 1 arranged below the connecting plate 11
The locked member 20 that connects the seat plate 4 disposed on the upper side of the lock member 1 is swingably penetrated.

Below the connecting plate 11, there is provided a supporting plate 6 rotatably mounted on the supporting shaft 5 and supporting the seat plate 4 while receiving the reaction force of the reaction applying mechanism 28. The support plate 6 has a mounting portion 13 rotatably fitted to the support shaft 5.
Locked member 2 penetrating through opening 12 of seat receiving member 3
0 and the seat plate 4 via the locked member 20.
And a locking end 14 for supporting the same.

The mounting portion 13 is a through hole in which an upper groove 6a formed at the front end of the support plate 6 and a lower groove 29a of a lower plate 29 screwed below the front end of the support plate 6 are opposed to each other. And For this reason, since the support plate 6 can be attached to the support shaft 5 so that the support shaft 5 is sandwiched between the support plate 6 and the lower plate 29, the support shaft 5 after being attached to the seat receiving member 3.
The support plate 6 can be attached to the rim. Further, each groove 6
Inside the a and 29a, sleeves 30, 30 made of, for example, a synthetic resin and divided vertically are provided. For this reason,
The rotation of the support plate 6 with respect to the support shaft 5 can be performed smoothly. In the present embodiment, the support plate 6 is attached to the support shaft 5 by sandwiching the support shaft 5 together with the lower plate 29 from above and below. However, the present invention is not limited to this. For example, as shown in FIGS. 6 may be perforated to form a mounting hole 13, and the support shaft 5 may be rotatably fitted into the mounting hole 13. Also in this case, the support plate 6 can be rotatably supported by the support shaft 5.

Further, the supporting plate 6 has a recess 15 for receiving the recess 11a of the connecting plate 11 so as to face the projecting rear side thereof, and a through hole 15a formed in the center of the recess 15.
And

A reaction force applying mechanism 28 is connected to the support plate 6 and the connecting plate 11. The reaction force applying mechanism 28 supports the seat plate 4 by urging the support plate 6 toward the initial position by urging the support plate 6 upward with respect to the connecting plate 11. The reaction force applying mechanism 28 is connected to the suspension screw 16 connected to the connecting plate 11.
And a spring mount 17 fixed to the suspension screw 16.
And a compression coil spring 2 interposed between the support plate 6 and the spring mount 17 and for urging the connecting plate 11 to press the support plate 6 via the spring mount 17 and the suspension screw 16. I have.

The hanging screw 16 is connected to the recess 11 of the connecting plate 11.
a through hole 11b of the support plate 6 and the through hole 15a of the recess 15 of the support plate 6 from above the recess 11a. The hanging screw 16 has a T-shaped head 16a and a screw portion 16b at the lower end.
And The head 16a enters the recess 11a. The diameter of each of the through holes 11b and 15a in the front-rear direction is slightly larger than the outer diameter of the suspension screw 16. Therefore, the suspension screw 16 can swing back and forth about the head 16a as shown in FIG.

The screw 16b of the suspension screw 16 has a bottom plate 1
A substantially cylindrical spring mount 17 having 7a is mounted. A nut 57 is fixed inside the center of the bottom plate 17a of the spring mount 17 by insert molding. The suspension screw 16 and the spring mount 17 are connected to the screw portion 16 b of the suspension screw 16 and the nut 57 of the spring mount 17.
It is attached by screwing. Therefore, by rotating the spring mount 17, the nut 57 moves up and down with respect to the screw portion 16b by a screw pair.
The mounting height of the spring mount 17 can be changed by its rotation. Further, a non-slip vertical groove 22 is formed on the outer peripheral surface of the spring mount 17 as shown in FIG. Therefore, the user can easily rotate the spring mount 17 without slipping.

The compression coil spring 2 is provided between the bottom plate 17 a of the spring mount 17 and the support plate 6 so as to surround the suspension screw 16. In the present embodiment, the source of the reaction force in the reaction force applying mechanism 28 is a compression coil spring. However, the present invention is not limited to this, and may be another elastic body such as a gas spring. The compression coil spring 2 urges the support plate 6 to press it against the back side of the connection plate 11. Then, the position of the seat plate 4 in a state where the compression coil spring 2 presses the support plate 6 against the back side of the connecting plate 11 is the initial position.

Here, by rotating the spring mount 17 and changing the mounting height of the bottom plate 17a, the bottom plate 17a compresses the compression coil spring 2 and changes the initial pressure.
The magnitude of the load required to rotate the support plate 6 can be adjusted. For this reason, since the magnitude of the force required for tilting the seat can be set to a strength according to the preference of the seated person, the sitting comfort can be improved.

Further, a seat is provided above the seat receiving member 3. The seat is generally composed of a seat plate 4 serving as a core material, a cushion (not shown) placed thereon, and an upholstery covering the cushion. A backrest (not shown) is provided at the rear of the seat, for example, by integral formation. Therefore, the seated person can lock the seat and the backrest by leaning on the backrest. The shape of the backrest is not particularly limited.

The seat plate 4 is supported at the left and right ends at the front by front supports 19, 19 rotatably fitted to both ends of the support shaft 5, and penetrates the opening 12 to form the support plate 6. The central portion is supported by the locked member 20 locked to the locking end 14.

The front support 19 is made of plastic and has, for example, a substantially C-shaped holding claw 19a which goes around the support shaft 5 from the front and back as shown in FIG. Nail 1
A plurality 9a is formed along the axial direction of the support shaft 5.
This makes it possible to reduce the rigidity of each of the holding claws 19a and facilitate the work of attaching the holding claws 19a to the support shaft 5. Then, when attaching the front supports 19, 19 to the support shaft 5, the seat plate 4 is pressed from above the support shaft 5, and the holding claws 19a are pushed and spread while being fitted with one touch. In the present embodiment, the front support 19 has a plurality of holding claws 19a along the axial direction of the support shaft 5, but is not limited thereto, and may have a single holding claw 19a. Also in this case, each front support 19 can be attached to the support shaft 5 with one touch.

The seat plate 4 is made of, for example, plastic.
It is formed integrally with the front supports 19, 19 by injection molding or the like. In the present embodiment, the seat plate 4 and the front supports 19, 19 are integrally formed by plastic injection molding. However, the present invention is not limited to this, and the seat plate 4 and the front supports 19, 19 are separately formed. Alternatively, they may be integrated by bonding or screwing. In the case of separate molding, for example, the seat plate 4, the front support 19,
One or both of the nineteen can be made of a metal having high rigidity and wear resistance. Here, when the front supports 19, 19 are made of high-rigidity metal, it is difficult to fit the front supports 19, 19 to the support shaft 5 with a single touch by the holding claws 19a. Then, the front supports 19, 19 and the seat plate 4 are fixed by screws or the like. Further, a through hole may be formed in the front supports 19, 19, and the support shaft 5 may be passed through the through holes, so that the front supports 19, 19 may be supported by the support shaft 5. Also in this case, the front supports 19, 19
Of the front supports 19, 1
9 and the seat plate 4 are fixed by screws or the like.

On the other hand, the locked member 20 supporting the central portion of the seat plate 4 includes a flange 31 having a through hole 31a through which a bolt for fastening to the seat plate 4 passes, and a locking end 1 of the support plate 6.
4 and a locking claw 32 which is hooked and locked at a lower portion of the lower portion 4. When the flange 31 is screwed to a position facing the opening 12 of the seat plate 4, the locked member 20
Are fixed to the seat plate 4. For this reason, the arrangement of the two front supports 19, 19 and the locked member 20 forms a vertex of a triangle as shown in FIGS. 1 and 9, so that the seat plate 4 is provided with the front supports 19, 19 and the locked member. It is supported with high stability on the seat receiving member 3 via the member 20, the support shaft 5 and the support plate 6. Then, the locking claw 32 of the locked member 20 is hooked below the locking end 14 of the support plate 6, so that the locked member 20 and the locking end 14 are integrated. For this reason,
Even if the chair is tilted forward when the seat plate 4 is not locked by the lock member 8, the seat plate 4 can be prevented from rising to the front.

In the present embodiment, the method of attaching the locked member 20 to the support plate 6 is such that the locking claw 32 of the locked member 20 is locked to the support plate 6, but is not limited to this. As shown in FIGS. 8 and 9, the locking member 20 is fixed by a set screw 23 passing through the through hole 14 a at the rear end of the support plate 6.
May be screwed to the support plate 6. Also in this case, even if the chair is tilted to the front side when the seat plate 4 is not locked by the lock member 8, the seat plate 4 can be prevented from rising to the front side. Further, the height of the locked member 20 is set to be, for example, substantially horizontal as an initial position when no load is applied to the seat and no load is applied. However, it is needless to say that the initial position is not limited to the horizontal position but may have an inclination angle.

The seat plate 4 and the locked member 20 are separate members and are integrated by screwing. For this reason,
The locked member 20 can be made of a metal having high rigidity. In this embodiment, the seat plate 4 and the locked member 20 are separate members. However, the present invention is not limited to this, and they may be integrally formed of, for example, plastic or metal.

Further, a plurality of engagement grooves 7,..., 7 are formed on the rear surface 20a of the locked member 20. The rear surface 20a is a convex cylindrical surface having the support shaft 5 as a center line. The locking member 8 is located behind the locked member 20.
Has been arranged. For this reason, the fitting length of the lock member 8 facing the engagement groove 7 into the engagement groove 7 can be made constant regardless of the swing angle of the seat plate 4. Can be surely fitted. In the present embodiment, the rear surface 20a of the locked member 20 is a convex cylindrical surface centered on the support shaft 5, but is not limited thereto, and may be a concave cylindrical surface centered on the support shaft 5. In this case, the locking member 8 is provided in front of the locked member 20.
Place. Also in this case, the fitting length of the lock member 8 into the engagement groove 7 can be made constant, so that the lock member 8
And the engagement groove 7 can be surely fitted.

The engagement grooves 7 of the member to be locked 20 have a horizontally long rectangular shape, and a plurality of engagement grooves 7 are arranged at intervals in the swinging direction of the seat plate 4, that is, in the vertical direction. The inner surface of each engagement groove 7 is flat. The number of the engagement grooves 7 is the number of positions where the tilt of the seat can be locked (that is, the number of steps). Further, the interval of formation of the engagement grooves 7 determines the inclination angle between the lock positions of the tilt of the seat. For this reason, the number and the interval of formation of the engagement grooves 7 are set in consideration of the operability of the chair to be applied.

The lock member 8 is slidably mounted on the seat receiving member 3 side, and is slidably engaged with the engagement groove 7.
, And locks the tilt of the seat plate 4 when it is fitted into the engagement groove 7. The lock member 8 is made of a plate material, and includes a lock portion 8a formed at the front end portion and capable of being fitted into the engagement groove 7, and an engagement hole 8b formed at the center portion and engaged with the urging means 24. have.

The lock member 8 has a leg receiving hole 9 of the seat receiving member 3.
The support walls 58, 58 formed on the left and right of the upper side of the front side are slidably supported by a slide support portion 58a in which the inside of the upper part is cut down stepwise. The cover plate 33 is screwed to the upper surfaces of the support walls 58, 58. Therefore, the locking member 8 is prevented from falling off from the sliding support portion 58a by the lid plate 33. Further, the lock member 8 is provided with support walls 58, 58.
In addition, the movement in the vertical direction is restricted by the lid plate 33. Further, the lock member 8 is supported movably back and forth at a position where the lock portion 8a can enter and exit the engagement groove 7. Then, when the lock member 8 slides forward, the lock portion 8a fits into the engagement groove 7. At this time, the lock member 8 is
Since the locking member 20 is located between the supporting members 58, 58 and the cover plate 33 and the engagement groove 7, the swing of the locked member 20 is limited by the support walls 58, 58 and the cover plate 33 via the locking member 8. When the locked member 20 cannot swing, the tilt of the seat is locked. When the lock member 8 slides rearward, the lock portion 8a comes off the engagement groove 7. At this time, since the locked member 20 can swing, the seat is unlocked and swingable.

The edges of the lock portion 8a and the engagement groove 7 are rounded and rounded. Therefore, even when the lock portion 8a is urged at a position slightly displaced up and down with respect to the engagement groove 7, the lock portion 8a is guided by the chamfered edge portion and is easily inserted into the engagement groove 7. Can be fitted.

In order to slide the lock member 8, the lock operation lever 18 connected to the lock member 8 via the urging means 24 is operated. The lock operation lever 18 has a shaft portion 37 as a first rotation shaft rotatably attached to the seat receiving member 3 and an operation portion 38 by which a user performs an operation of switching a locked state. The shaft portion 37 is the seat receiving member 3
Through the through hole formed in the lower portion of the support wall 58. Thus, the shaft 37 is rotatably supported by the support wall 58. The tip of the shaft 37 has a shaft 37
Is formed.
A flange 39 is formed on the distal end side of the engagement groove 40 in the axial direction. A fitting section 41 having a substantially rectangular cross section is formed on the operation section 38 side of the engagement groove section 40.

The operation section 38 is provided to bend forward with respect to the shaft section 37. The tip of the operation section 38 is located near the support shaft 5. That is, the distal end of the operation unit 38 is located near the swing center of the seat plate 4. For this reason, the position of the tip of the operation portion 38 hardly changes regardless of the inclination angle of the seat, so that almost constant operability can be maintained.

The lock operation lever 18 and the lock member 8
The urging means 24 is interposed between the two. Urging means 2
4 slides the lock member 8 by elastically transmitting the rotation of the lock operation lever 18 to the lock member 8.

The urging means 24 includes a switching arm 42 which engages with the lock member 8 in the sliding direction of the lock member 8.
And a switching lever 34 that is interlocked with the lock operation lever 18 and is switched between the locked position and the unlocked position and held.
And a biasing spring 43 which is an elastic body interposed between the switching lever 34 and the switching arm 42, and a holding member 35 for holding the switching lever 34 in the locked position and the unlocked position. The urging means 24 is provided on the support wall 5 of the seat receiving member 3.
It is housed in a housing part 44 consisting of a space between 8, 58. Then, the lid plate 33 is put on the upper side of the housing portion 44 and screwed. An escape hole 33a formed of a rectangular through hole is formed at the center of the cover plate 33. Thus, the switching arm 42 which jumped upward exits the engaging hole 8b of the locking member 8 is prevented from interfering with the cover plate 33.

The switching arm 42 is engaged with the engagement hole 8b of the lock member 8 and is oscillated by the urging spring 43 to move the lock member 8 back and forth. The switching arm 42 has a substantially channel-like shape as a whole, and has coaxial circular through holes 42a, 42a formed at two base ends.
And an engaging portion 42b formed by connecting two tip portions to each other. Each through-hole 42 a is rotatably attached to the shaft 37 of the lock operation lever 18. The engagement portion 42b is fitted in the engagement hole 8b of the lock member 8.
Therefore, when the switching arm 42 rotates and the engagement portion 42b moves forward, the lock member 8 slides forward and fits into the engagement groove 7. When the switching arm 42 rotates and the engagement portion 42b moves rearward, the lock member 8 slides rearward and comes off the engagement groove 7.

In this embodiment, since the switching arm 42 is interposed between the lock member 8 and the urging spring 43, the urging force from the urging spring 43 to the lock member 8 can be smoothly transmitted. it can. In the present embodiment, the switching arm 42 is interposed between the lock member 8 and the urging spring 43. However, the present invention is not limited to this, and the lock member 8 and the urging spring 43 may be directly connected. Also in this case, the urging force of the urging spring 43 can be transmitted to the lock member 8.

The switching lever 34 is a lock operation lever 18.
It is integrated with and works together. The switching lever 34 has a support hole 34a formed of a square hole. This support hole 34a
Is fitted to the fitting portion 41 of the shaft portion 37 of the lock operation lever 18. The shape and size of the support hole 34a and the cross section of the fitting portion 41 are the same. Thereby, the switching lever 34 and the lock operation lever 18 rotate integrally. Therefore, the user operates the lock operation lever 1
When the operation section 38 of FIG. 8 is operated, the fitting section 41 of the shaft section 37 rotates to rotate the switching lever 34.

The switching lever 34 is switched between a locked position and an unlocked position by operating the lock operating lever 18 and is held by the holding member 35 at either the locked position or the unlocked position. Here, the lock position means a position where the switching lever 34 and the lock operation lever 18 are positioned so that the urging means 24 elastically urges the lock member 8 in the direction of fitting into the engagement groove 7. Further, the unlocking position means that the urging means 24 is
Means a position where the switching lever 34 and the lock operation lever 18 are positioned so as to elastically urge in the direction of being pulled out from the engagement groove 7.

The holding member 35 includes the head 3 of the switching lever 34.
By engaging with 4b, the switching lever 34 is held at either the locked position or the unlocked position. The holding member 35 has a lock groove 35 that elastically locks and holds the head 34b so that the switching lever 34 is located at the lock position.
a and an unlock groove 35b for elastically locking and holding the head 34b so that the switching lever 34 is located at the unlock position. The holding member 35 is made of plastic and is integrally formed by injection molding. For this reason, by rotating the switching lever 34 held in one of the lock groove 35a and the unlock groove 35b, the head 34b pushes the edge of the groove outward, pushes and expands the holding member 35, and rotates the other groove. You can get into it. As a result, the switching lever 34 can be switched between the locked position and the unlocked position, and is held at any one of the positions.

An engaging claw 35c for attaching the holding member 35 to the seat receiving member 3 is formed below the holding member 35. This locking claw portion 35c has two horizontal claws positioned vertically. A downward projection is formed at the tip of the upper claw. On the other hand, a mounting portion 59a for mounting the locking claw 35c is formed at the front of the base block 59 of the seat receiving member 3. The mounting portion 59a has a hole for accommodating the lower claw and a recess for locking the projection at the tip of the upper claw. Mounting part 59a
When attaching the locking claw 35c to the locking claw 35c, the lower claw of the locking claw 35c is accommodated in the hole of the mounting portion 59a, and then
The protrusion at the tip of the upper claw of 5c is locked in the recess of the mounting portion 59a. Accordingly, the holding member 35 can be easily attached to the seat receiving member 3 with one touch without using another member such as a bolt.

In this embodiment, the elasticity of the plastic holding member 35 is used for positioning the switching of the switching lever 34. However, the present invention is not limited to providing the holding member 35 with elasticity. The switching lever 34 may be provided with a plunger as a rigid body and the switching member may be positioned by pressing the holding member 35. Also,
In the present embodiment, the lock groove 35a and the unlock groove 35b are formed on the holding member 35 side. However, the present invention is not limited to this, and as shown in FIG.
d and the unlock groove 34e may be formed, and these grooves 34d, 34e may be pressed by, for example, a plunger 60 formed in the base end block 59 to perform switching positioning. In this case, the holding member 35 can be omitted. Further, it is a matter of course that the switching position of the switching lever 34 may be determined by means other than these.

The biasing spring 43 is an elastic body interposed between the switching lever 34 and the switching arm 42, and controls the rotation of the lock operation lever 18 transmitted via the switching lever 34 via the switching arm 42. The lock member 8 is slid by transmitting elastically to the lock member 8.

The biasing spring 43 employs a torsion coil spring in this embodiment. The biasing spring 43 is wound around the shaft 37 of the lock operation lever 18 in a space inside the switching arm 42. Both ends of the biasing spring 43 are straight portions 43a, 43a in which the ends of the wound wire are straightened along the tangential direction of the winding, and each straight portion 43a, 43a.
Are bent so as to be parallel to the axial direction of the biasing spring 43 and to be opposite to each other. The one hook 43b is connected to the switching arm 42.
Are locked in through holes 42c formed in a part of. Also, the other hook 43b is connected to the head 34b of the switching lever 34.
Is locked in a through hole 34c formed in a part thereof. Therefore, the twisting force is transmitted so that the switching arm 42 is rotated in the same direction by the rotation of the switching lever 34.

Here, when the lock member 8 is fitted into the engagement groove 7 and no external force acts on the seat plate 4 and receives a reaction force by the reaction force applying mechanism 28, the lock member 8 is pulled out of the engagement groove 7. Of the switching lever 3 and the frictional force required for
The urging force of the urging spring 43 is set to be smaller than the force for holding the lock member 4 at the lock position or the unlock position. For this reason, the locking member 8 is
When the switching arm 42 cannot rotate due to movement of the urging spring 4, only the switching lever 34 is rotated to
3 is charged. Further, even if the urging force of the urging spring 43 attempts to rotate the switching lever 34, the holding member 35 holds the position of the switching lever 34 because the holding force of the holding member 35 is stronger, and the urging spring 43 is stored. Be inspired.

On the other hand, the seat receiving member 3 has the leg 25 in the leg receiving hole 9.
Are supported by the legs 25 by fitting the upper ends of them. A gas spring is provided at the upper end of the leg 25. The adjustment pin 45 of the gas spring projects from the upper end of the leg 25. Therefore, by pressing the adjustment pin 45, the flow of the fluid in the gas spring becomes free, and the length of the gas spring becomes variable. Further, by releasing the pressing of the adjustment pin 45, the length of the gas spring can be fixed. Thereby, the length of the leg 25 can be changed and fixed.

In the vicinity of the adjusting pin 45 of the gas spring, a pressing mechanism 46 for pressing the adjusting pin 45 is provided, which is a mechanism different from the locking device 1. The pressing mechanism 46 has a pressing arm 47 that can push down the adjustment pin 45 by rotation, and a seat height operation lever 48 that rotates the pressing arm 47.

The seat height operation lever 48 has a shaft portion 49 rotatably supported by the seat receiving member 3 and an operation portion 51 for enabling a user to change the seat height. The seat height operation lever 48 and the lock operation lever 18 are connected to the respective shaft portions 3.
7, 49 are arranged coaxially and the ends are arranged close to each other. The operating part 5 bent forward is provided on the shaft part 49.
1 are integrated. The shaft portion 49 penetrates through a through hole formed in a lower portion of the support wall 58 of the seat receiving member 3. Thus, the shaft 49 is rotatably supported by the support wall 58. At the tip of the shaft 49, an engagement groove 53 is formed, which is a groove that goes around the shaft 49. A flange 52 is formed on the distal end side of the engagement groove 53 in the axial direction. A fitting section 50 having a substantially rectangular cross section is formed on the operation section 51 side of the engagement groove 53.

The operation section 51 is provided to bend forward with respect to the shaft section 49. The tip of the operation unit 51 is located near the support shaft 5. That is, the distal end of the operation unit 51 is located near the swing center of the seat plate 4. For this reason, the position of the tip of the operation unit 51 hardly changes regardless of the inclination angle of the seat, so that almost constant operability can be maintained.

The pressing arm 47 has a substantially channel-like shape as a whole, and has coaxial through holes 47a, 47a formed at two base ends and a pressing portion 47b connecting the two distal ends. And These through holes 47a, 4
7a is supported by the shaft portions 37 and 49, respectively. Here, the through hole 47 a supported by the shaft portion 49 of the seat height operation lever 48 is a square hole, and is fitted into the fitting portion 50 of the shaft portion 49. Then, the seat height operation lever 48 and the pressing arm 47 rotate integrally. On the other hand, the through hole 47a supported by the shaft portion 37 of the lock operation lever 18 is a round hole,
The shaft 37 is rotatably fitted to a cylindrical portion of the shaft 37 by filling a gap. Therefore, the pressing arm 47 is rotated by the operation of the seat height operation lever 48 and is not affected by the operation of the lock operation lever 18. In addition, since the pressing arm 47 is supported at two points by the seat height operation lever 48 and the lock operation lever 18, it is possible to prevent the pressing arm 47 from being twisted when the seat height operation lever 48 is operated.

The pressing portion 47b is located in contact with the upper part of the adjustment pin 45. Therefore, when the pressing portion 47b is lowered by operating the pressing arm 47, the adjustment pin 45 is pressed down. Further, when the operation of the pressing arm 47 is released, the adjustment pin 45 is raised to push up the pressing portion 47b.

Further, there is provided a connecting means 54 for rotatably connecting the ends of the shaft portions 37 and 49 of the lock operation lever 18 and the seat height operation lever 48 at the same time. The connecting means 54 has a substantially channel-like shape, and has two claws 55, 55 at two end portions. Each nail 5
A U-shaped groove is formed between 5,55. Then, the connecting means 54 covers the distal ends of the shafts 37, 49, and the claws 55, 55 are rotatably fitted so as to sandwich the engaging grooves 40, 53 of the shafts 37, 49. As a result, the shaft portions 37 and 49 are axially connected to each other while being rotatable. For this reason, since a plurality of rotation shafts can be prevented from falling off by a single member, the number of parts can be reduced. Further, in the present embodiment, each shaft portion 37, 49
Are coaxial and arranged with their ends close to each other, so that the connecting means 54 can be made smaller. For this reason, the size of the locking device 1 can be reduced.

Further, the connecting means 54 is accommodated in a connecting means accommodating portion 56 formed inside a support wall 58 of the seat receiving member 3 on the side of the sitting height operation lever 48. For this reason, since the connection means 54 is restricted from moving in the axial direction of the shafts 37 and 49 inside the connection means accommodating portion 56, even if an external force in the axial direction acts on the shafts 37 and 49, the connection 37, 49 can be prevented from moving.

The upper part of the connecting means housing part 56 is open. When assembling the connecting means 54, the engaging grooves 40, 53 of the shafts 37, 49 are connected to the connecting means accommodating section 5.
The coupling means 54 is inserted from above in a state where the claws 55 and 55 are located in the inside of each of the engagement grooves 40 and 53, and the claws 55 and 55 are attached to the respective engagement grooves 40 and 53. Further, the lock member 8
Are arranged. For this reason, even if the connecting means 54 tries to jump out of the connecting means accommodating portion 56 when the chair is turned upside down, the connecting means 54 abuts on the lock member 8, so that the jumping out can be prevented.

When the above-described locking device 1 is in the unlocked state, when a load is applied so as to lean against the backrest and tilt the seat backward, the seat plate 4 rotates backward about the support shaft 5. At this time, the locked member 20 is
The support plate 6 is pushed down around the center. Thereby, the support plate 6
Rotates backward about the support shaft 5 to compress the compression coil spring 2 and generate a reaction force. Here, when the support plate 6 rotates and changes the angle with respect to the seat receiving member 3, the compression coil spring 2
The direction of pushing down changes. Due to this change, the compression coil spring 2, the spring mount 17, and the suspension screw 16 tilt forward (illustrated by a two-dot chain line in FIG. 1). The seat is inclined rearward while receiving the reaction force of the compression coil spring 2, so that the seat can be locked.

When the load on the seat is smaller than the reaction force of the compression coil spring 2, the compression coil spring 2 pushes up the support plate 6 until it comes into contact with the connecting plate 11, so that the seat is returned to the horizontal initial position.

To lock the tilt of the seat, the shaft 37 is rotated clockwise in FIG. 1 by turning the lock operation lever 18 so as to depress it, and the head 34b of the switching lever 34 is unlocked. It is moved from the groove 35b to the lock groove 35a to be locked and held at the lock position. The rotation of the head 34b urges the lock member 8 via the urging spring 43 so as to protrude toward the locked member 20. At this time, if any of the engagement grooves 7 of the locked member 20 is at the same height as the sliding surface of the lock member 8, the lock portion 8a is inserted into the engagement groove 7 as it is.

When the engaging groove 7 of the locked member 20 is displaced from the height of the locking member 8, the tip of the locking portion 8a comes into contact with the rear surface 20a of the locked member 20 and is inserted into the engaging groove 7. Since the biasing spring 43 is twisted, the rotation of the switching lever 34 is allowed. Accordingly, the lock member 8 is held in a state of being pressed toward the locked member 20 by receiving the spring force of the urging spring 43. Therefore, when the seat is slightly tilted and the lock portion 8a is at the same height as the engagement groove 7, it is pushed into the engagement groove 7 by a spring force so as to slide into the engagement groove 7. Therefore, the operability can be improved because it is not necessary to keep pressing down the operation unit 38 until the locking operation is completed.

Further, since the edges of the lock portion 8a and the engagement groove 7 are chamfered, the lock portion 8a can be easily fitted into the engagement groove 7. When the lock portion 8a is fitted into the engagement groove 7, the lock member 8 is
Since the rocking member 20 exists between the engaging portions 8 and 58 and the cover plate 33 and the engaging groove 7 to limit the swing of the locked member 20, the tilt of the seat can be locked.

When the seat is unlocked, the operating portion 38 of the lock operating lever 18 is pushed up,
The shaft 37 is rotated in the counterclockwise direction in FIG. 1 to move the head 34b of the switching lever 34 from the lock groove 35a to the unlock groove 35b and hold it. By the rotation of the head 34b, the lock member 8 is engaged with the engagement groove 7 via the urging spring 43.
Energize in the direction to get out of.

At this time, if a person is seated and the weight is acting on the seat, the weight and the reaction force of the reaction force applying mechanism 28 are balanced, and a large friction is generated between the engagement groove 7 and the lock portion 8a. Since no force is generated, the lock member 8 comes out of the engagement groove 7 to release the lock. Therefore, the locked member 20 and thus the seat can swing.

Further, even if the lock operation lever 18 is turned to the unlock side in a state where no person is seated, the lock portion 8a and the locked member accommodated in the engagement groove 7 by the reaction force of the reaction force applying mechanism 28. A large frictional force is generated between the lock member 8 and the lock member 8 to maintain the state in which the lock member 8 is inserted into the engagement groove 7. For this reason, a self-holding state in which the position of the seat is held as it is is obtained. Therefore, even if the lock operation lever 18 is operated to the unlock side when there is no occupant, it is possible to prevent the seat and the backrest from jumping up suddenly.
Further, when a person sits on the seat in the self-holding state, the weight of the occupant and the reaction force of the reaction force applying mechanism 28 are balanced, and the frictional force applied to the lock member 8 is eliminated. (Unlocked state), and the locked member 20 and thus the seat can be swung.

According to the locking device 1 of the present embodiment,
Since the self-holding function is realized by a simple mechanism, the self-holding function can be provided without greatly increasing the number of parts as compared with a conventional chair having no self-holding function. For this reason, it is possible to have a self-holding function while suppressing the complexity of the manufacturing process of the chair and the manufacturing cost to the same level as before.

Further, according to the locking device 1 of the present embodiment, the locked member 20 has the locking function of locking the tilt of the seat by the fitting of the locking member 8 and the seating member 20 interposed between the seat plate 4 and the support plate 6. And a locking function that supports and locks. Therefore, the number of parts can be reduced by sharing the members. In the present embodiment, the locked member 20 has both the locking function of tilting the seat and the locking function of the seat. However, the present invention is not limited to this, and the locked member 20 has only the locking function of tilting the seat. Alternatively, the locking function of the seat may be performed by another mechanism.

The above embodiment is an example of a preferred embodiment of the present invention, but the present invention is not limited thereto, and various modifications can be made without departing from the gist of the present invention. For example, in the above-described embodiment, the locked member 2
0 is fixed to the seat, and the lock member 8, the lock operation lever 18, and the urging means 24 are attached to the seat receiving member 3. However, the present invention is not limited to this. The lock member 8, the lock operation lever 18, and the urging means 24 may be attached to the seat plate 4 by directly connecting the lock member 8 to the seat receiving member 3 while connecting the lock member 8 directly to the seat plate 4. In this case, since the lock operation lever 18 moves together with the swinging seat plate 4, the relative position between the seat and the lock operation lever 18 can always be kept constant regardless of the inclination angle of the seat. For this reason, when the lock operation lever 18 is provided on the side portion of the seat, for example, where the relative movement amount between the seat and the seat receiving member 3 is large, the operability can be improved as compared with the case where the lock operation lever 18 is provided on the side portion of the seat receiving member 3. .

In the above-described embodiment, the locked member 20 is fixed to the seat plate 4 and the support plate 6 and the lock member 8 is attached to the seat receiving member 3 so as to be movable back and forth. The lock member 20 may be attached to the seat plate 4 so as to be able to move back and forth without being fixed to the support plate 6, and the lock member 8 may be fixed to the seat receiving member 3. The lock operation lever 18 and the urging means 24 are provided on the seat plate 4 similarly to the embodiment shown in FIG. 11 so as to move the locked member 20 back and forth. According to this locking device 1,
Even if the lock operation lever 18 is turned to the unlock side, a large frictional force is generated between the lock portion 8a accommodated in the engagement groove 7 and the locked member 20 due to the reaction force of the reaction force applying mechanism 28, and the lock member Since the state in which the seat 8 is inserted into the engagement groove 7 is maintained, a self-holding state in which the position of the seat is held as it is can be achieved.

Further, in the above embodiment, the urging means 2
A biasing spring 43 comprising a torsion coil spring as the elastic body of No. 4.
However, the present invention is not limited to this, and an elastomer such as rubber may be used. For example, as shown in FIG. 12, the urging means 24 is fitted to the fitting portion 41 of the shaft portion 37 and integrally rotates around the fitting member 61. An elastic portion 62 as an elastic body made of an elastomer such as rubber, a switching arm 42 integrated around the elastic portion 62 and engaged with the lock member 8;
And the same switching lever and holding member (not shown) as in the embodiment shown in FIG. Also in this case, the rotation of the lock operation lever 18 can elastically urge the lock member 8 in the same direction. As shown in FIG. 13, the urging means 24 is made of an elastomer such as rubber or the like, which is made of an elastomer such as rubber and engages with the lock member 8 while rotating integrally with the fitting part 41 of the shaft part 37 and the switching arm. And a switching lever and a holding member (not shown) similar to those of the embodiment shown in FIGS. 1 to 9. Also in this case, the rotation of the lock operation lever 18 can elastically urge the lock member 8 in the same direction.

In the above embodiment, the switching lever 3
4 is rotated in any direction, the rotation is
However, the rotation is not limited to this, and the rotation is only performed when the switching lever 34 is rotated in a direction in which the lock member 8 is pulled out from the engagement groove 7, and the rotation is transmitted to the urging spring 43. May be transmitted to the switching arm 42 via the. For example, as shown in FIG. 14, a projection 34 abuts on the switching lever 34 against the rear surface of the switching arm 42.
Form f. Further, the end of the biasing spring 43 on the switching arm 42 side is hooked on the front side of the switching arm 42. Thus, when the switching lever 34 is rotated in a direction in which the lock member 8 is pulled out of the engagement groove 7, this rotation is performed by the urging spring 43.
Is transmitted to the switching arm 42 through the lock member 8.
When the switching lever 34 is rotated in the direction in which the switching arm 34 is inserted into the engagement groove 7, the projection 34f of the switching lever 34 comes into contact with the rear surface of the switching arm 42 and directly pushes the switching arm 42 forward. Even in this case, if the lock operation lever 18 is operated to the unlock side when there is no occupant, the seat is held by itself, so that it is possible to prevent the seat and the backrest from jumping up suddenly.

Further, in the above-described embodiment, each shaft 3
Although 7, 49 are arranged coaxially with their respective ends close to each other, the present invention is not limited to this. For example, each end may be arranged near each other at an angle such as a right angle. Also in this case, the size of the locking device 1 can be reduced. Further, in the present embodiment, the seat height operation mechanism 46 is adopted as another mechanism, but the present invention is not limited to this, and may be a mechanism using another rotating shaft such as an armrest rocking device. Also in this case, the two rotating shafts can be connected by the connecting means 54. In this embodiment, the claws 55 and 55 are provided at two places of the connecting means 54 to connect the two shaft portions 37 and 49. However, the present invention is not limited to this, and the pawls 55 are provided at three or more places of the connecting means 54. , 55 may be provided to connect three or more rotating shafts. Also in this case, the size of the locking device 1 can be reduced. In this embodiment, two shafts 3 are used.
7, 49 are connected by a single connecting means 54,
However, the present invention is not limited thereto, and a separate member may be attached to each of the shaft portions 37 and 49 to prevent the shaft portions 37 and 49 from falling off from the seat receiving member 3.

Further, in the above-described embodiment, the surface where the engagement groove 7 and the lock member 8 come into contact with each other when the seat is self-held is made flat. However, the present invention is not limited to this, and as shown in FIG. A step may be formed on the surface where the groove 7 and the lock member 8 are in contact with each other so as to be hooked to each other. In this case, the load at which the self-holding is released can be easily changed by adjusting the height of the step portion when the engagement groove 7 or the lock member 8 is manufactured.

In the above-described embodiment, the supported member is the seat and the support member is the seat receiving member 3. However, the present invention is not limited to this, and one member swings around one rotation shaft so as to sandwich it. The present invention can be applied to all locking mechanisms including a supporting member and a supported member that are constantly urged in a direction in which the included angle increases between two moving members. For example, the supported member may be a backrest or an armrest, and the supporting member may be these supporting members. In this case, when the operation lever is operated to the unlock side when there is no occupant, the backrest and the armrest are self-held, so that the backrest and the armrest can be prevented from jumping up suddenly.

In the above-described embodiment, the source of the reaction force of the reaction force applying mechanism 28 is the compression coil spring 2. However, the present invention is not limited to this and may be a torsion bar. In this case, by fixing the central portion of the support shaft 5 and the support plate 6 by also using the torsion bar as the support shaft 5, the torsion bar can be twisted by the rotation of the support plate 6 to accumulate energy. According to this, the degree of freedom in the design of the chair can be increased, and the number of parts can be reduced.

Further, in the above-described embodiment, the support shaft 5 is formed of a single rod projecting to the left and right of the seat receiving member 3. However, the present invention is not limited to this. Things. Also in this case, the seat receiving member 3 can support the seat plate 4 and the support plate 6.

On the other hand, in the embodiment described above, the support shaft 5 is fixed to the seat receiving member 3 and the support plate 6 is rotatably supported. However, the present invention is not limited to this, and the support plate 6 is fixed to the support shaft 5. The support shaft 5 itself may be rotatably supported by the seat receiving member 3.

Further, in each of the above embodiments, the locking device is applied to the rocking chair. However, the present invention is not limited to this. The present invention can be applied to all types in which a member and a member are swung about a rotation axis. For example, it can be used for a table of a personal computer desk or a drafting table which is quite heavy. Since such a table top has a considerable weight, a large reaction force is applied to balance the table top. In this case, when the operation lever is operated to the unlock side when no load is applied to the table plate, the table plate is held by itself, so that it is possible to prevent a phenomenon that the table plate jumps rapidly.

[0090]

As is apparent from the above description, according to the chair locking device of the first aspect, even when the operating means is operated to the unlock position when no external force is applied to the supported member, the chair is locked. Since the position of the supporting member is held as it is, the supported member can be prevented from suddenly jumping up. Moreover, since the mechanism is simple, the manufacturing cost and the complexity of the manufacturing process can be suppressed as compared with a conventional locking device having no self-holding mechanism.

According to the locking device of the second aspect, even if the lock member is displaced from the engagement groove and cannot be fitted when the operating means is operated to the lock position, the urging means can be used. It is not necessary to manually maintain the operating state of the operating means until the locking operation is completed. Therefore, the operability of the locking operation can be improved.

Furthermore, according to the locking device of the third aspect, the supported member can be self-held by the elastic body.

Further, according to the locking device of the fourth aspect, the function of operating the operating means on the first rotating shaft and the second function while preventing the first rotating shaft and the second rotating shaft from falling off. And the function of supporting the arm operated by the rotating shaft of the present invention. This makes it possible to reduce the number of components required for mounting the rotating shaft, thereby reducing the size and weight of the locking device.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view showing a locking device of the present invention.

FIG. 2 is a plan view showing a locking device.

FIG. 3 is a bottom view showing the locking device.

FIG. 4 is a plan view showing a main part of the locking device.

FIG. 5 is a longitudinal sectional rear view showing a main part of the locking device.

FIG. 6 is an exploded view showing a main part of the locking device.

FIG. 7 is an exploded view showing the urging means.

FIG. 8 is an exploded view showing another embodiment of the locking device.

FIG. 9 is a perspective view showing another embodiment of the locking device.

FIG. 10 is a side view showing another embodiment of the switching lever.

FIG. 11 is a schematic longitudinal sectional side view showing another embodiment of the locking device.

FIG. 12 is a side view showing another embodiment of the urging means.

FIG. 13 is a side view showing another embodiment of the urging means.

FIG. 14 is a perspective view showing still another embodiment of the urging means.

FIG. 15 is a vertical cross-sectional side view showing a fitted state of a lock member and an engagement groove.

FIG. 16 is a side view showing a conventional locking device.

FIG. 17 is a side view showing another conventional locking device.

FIG. 18 is a perspective view showing another conventional locking device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Locking device 3 Seat receiving member (support member) 4 Seat plate (supported member) 7 Engagement groove 8 Lock member 18 Lock operation lever (operating means) 20 Locked member 24 Energizing means 28 Reaction force imparting mechanism 37 Shaft (First rotating shaft) 43 Urging spring (elastic body) 46 Seating height operation mechanism (another mechanism) 49 Shaft (second rotating shaft) 54 Connecting means 62 Elastic part (elastic body) 63 Elastic arm (elastic body) , Switching arm)

Claims (4)

(57) [Claims] 1. A locking device for supporting a supported member so as to be able to swing about one rotation axis with respect to the support member and urging the supported member toward an initial position by a reaction force applying mechanism. A locked member having a plurality of engagement grooves arranged in a swinging direction of the supported member and attached to one of the support member and the supported member; and the support member or the supported member. A lock member which is slidably mounted in a direction in which the locked member is not attached and which slides in and out of the engagement groove and locks the tilting of the supported member when the locked member is fitted into the engagement groove; An operating means switched between a locked position and an unlocked position and held at least in the unlocked position; and an operating means provided between the operating means and the lock member, Transmitting the movement to the lock member,
And a biasing means for elastically biasing the lock member at least in a direction in which the lock member is extracted from the engagement groove. 2. A method position capable of holding the holding member in any of the previous SL said lock position and said unlock position operating means
2. The apparatus according to claim 1, wherein said urging means elastically urges the lock member in both a direction in which the lock member is extracted from the engagement groove and a direction in which the lock member is inserted into the engagement groove.
A locking device as described. 3. A switching arm which engages with the lock member in a sliding direction of the lock member, and is held between the lock position and the unlock position in conjunction with the operation means. A switching lever, an elastic body interposed between the switching lever and the switching arm, and a holding member for holding the switching lever in the locked position and the unlocked position. Item 3. The locking device according to Item 1 or 2. 4. A first rotating shaft which rotates integrally with the operating means, a second rotating shaft which is arranged coaxially with the first rotating shaft and an end near each other, and An arm that rotates integrally with the rotation shaft of the first rotation shaft and is rotatably supported by the first rotation shaft; and a connecting unit that rotatably connects the ends of the rotation shafts. 1
The locking device according to any one of claims 1 to 3.